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A case-based method of selecting covariates for digital soil mapping

Journal of Integrative Agriculture 2020年第8期19卷 2127-2136页

作者： LIANG Peng QIN cheng-zhi ZHU A-xing hou Zhi-wei FAN Nai-qing WANG yi-jie State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101P.R.China University of Chinese Academy of Sciences Beijing 100049P.R.China Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application School of GeographyNanjing Normal UniversityNanjing 210097P.R.China Key Laboratory of Virtual Geographic Environment Ministry of EducationNanjing Normal UniversityNanjing 210023P.R.China Department of Geography University of Wisconsin-MadisonMadisonWI 53706USA

Selecting a proper set of covariates is one of the most important factors that influence the accuracy of digital soil mapping(DSM).The statistical or machine learning methods for selecting DSM covariates are not available for those situations with limited *** solve the problem,this paper proposed a case-based method which could formalize the covariate selection knowledge contained in practical DSM *** proposed method trained Random Forest(RF)classifiers with DSM cases extracted from the practical DSM applications and then used the trained classifiers to determine whether each one potential covariate should be used in a new DSM *** this study,we took topographic covariates as examples of covariates and extracted 191 DSM cases from 56 peer-reviewed journal articles to evaluate the performance of the proposed case-based method by Leave-One-Out cross *** with a novices’commonly-used way of selecting DSM covariates,the proposed case-based method improved more than 30%accuracy according to three quantitative evaluation indices(i.e.,recall,precision,and F1-score).The proposed method could be also applied to selecting the proper set of covariates for other similar geographical modeling domains,such as landslide susceptibility mapping,and species distribution modeling.

关键词： digital soil mapping covariates case-based reasoning Random Forest

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Car-Parinello molecular dynamics simulations of thionitroxide and S-nitrosothiol in the gas phase,methanol,and water——A theoretical study of S-nitrosylation

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Science China Chemistry 2012年第10期55卷 2081-2088页

作者： LIANG Juan cheng ShangLi hou JunWei XU ZhenHao ZHAO yi-Lei State Key Laboratory of Microbial Metabolism School of Life Sciences and BiotechnologyShanghai Jiao Tong University Shanghai 200240China Shanghai Center for Systems Biomedicine Shanghai Jiao Tong UniversityShanghai 200240China MOE Laboratory of Scientific and Engineering Computing Shanghai Jiao Tong UniversityShanghai 200240China

A dilemma about whether thionitroxide radical (RSNHO) or S-nitrosothiol (RSNO) is observed in protein S-nitrosylation has arisen recently. To illustrate the effect of chemical environment on these structures, this paper presents quantum mechanical molecular dynamics of thionitroxide, and cis-and trans-S-nitrosothiols in the gas phase, methanol, and water. By using Car-Parrinello molecular dynamics (CPMD), we have observed that there is free rotation about the S-N bond at 300 K in thionitroxide, but no such rotation is observed for S-nitrosothiol. The C-S-N-O torsion angle distribution in thionitroxide is s-ignificantly dependent upon the surrounding environment, leading to either gauche-, cis-, or trans-conformation. In the case of S-nitrosothiol the C-S-N-O plane is twisted slightly by 5°-15° in the cis-isomer, while the periplanar structure is well-retained in the trans-isomer. The calculated results are in agreement with the X-ray crystallographic data of small molecular RSNO species. Interestingly, for both compounds, the CPMD simulations show that solvation can cause a decrease in the S-N bond length. Moreover, the oxygen atom of thionitroxide is found to be a good hydrogen-bond acceptor, forming an oxyanion-hole-like hydrogen bonding network.

关键词： quantum mechanical molecular dynamics S-nitrosylation thionitroxide S-nitrosothiol solvent effect

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An efficient GPU-based parallel tabu search algorithm for hardware/software co-design

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Frontiers of Computer Science 2020年第5期14卷 135-152页

作者： Neng hou Fazhi He yi Zhou yilin Chen School of Computer Science Wuhan UniversityWuhan430072China School of Computer Science Yangtze UniversityJingzhou434023China School of Information Science and Engineering Wuhan University of Science and TechnologyWuhan430081China

Hardware/software partitioning is an essential step in hardware/software *** large size problems,it is difficult to consider both solution quality and *** paper presents an efficient GPU-based parallel tabu search algorithm(GPTS)for HW/SW partitioning.A single GPU kernel of compacting neighborhood is proposed to reduce the amount of GPU global memory accesses theoretically.A kernel fusion strategy is further proposed to reduce the amount of GPU global memory accesses of *** further minimize the transfer overhead of GPTS between CPU and GPU,an optimized transfer strategy for GPU-based tabu evaluation is proposed,which considers that all the candidates do not satisfy the given *** show that GPTS outperforms state-of-the-art work of tabu search and is competitive with other methods for HW/SW *** proposed parallelization is significant when considering the ordinary GPU platform.

关键词： hardware/software co-design hardware/software partitioning graphics processing unit GPU-based parallel tabu search single kernel implementation kernel fusion strategy optimized transfer strategy

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Rare-earth dialkyl and dihydride complexes bearing monoanionic ancillary ligands

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Science China Chemistry 2011年第12期54卷 2032-2037页

作者： cheng JianHua hou ZhaoMin Organometallic Chemistry Laboratory RIKEN Advanced Science Institute 2-1 Hirosawa Wako Saitama 351-0198 Japan

Rare-earth elements, including scandium, yttrium, and the lanthanides （La-Lu）, possess unique chemical and physical properties, and constitute one of the last frontiers in the periodic table. Rare-earth elements are... 详细信息

关键词：稀土元素复合物轴承配体二氢烷基化学性质香格里拉

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Nonlinear resonance characteristics of a dual-rotor system with a local defect on the inner ring of the inter-shaft bearing

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Chinese Journal of Aeronautics 2021年第12期34卷 110-124页

作者： Haiming yi Lei hou Peng GAO Yushu CHEN School of Astronautics Harbin Institute of TechnologyHarbin 150001China

In this paper,the nonlinear resonance characteristics of a dual-rotor system are investigated with the consideration of a local defect on the inter-shaft bearing of the system.A simplified model of the dual-rotor system is proposed by considering that there is a local defect on the inner ring of inter-shaft *** local defect is modelled as an inverted isosceles trapezoidal groove,which can make great influence on the inter-shaft bearing force due to the change of radial clearance of the inter-shaft *** motion equations of the dual-rotor system are formulated by using the Lagrange *** Runge-Kutta method is employed to solve the motion *** amplitude-frequency response curve of the dual-rotor system is obtained,the abnormal resonance characteristics are *** addition,the influence of defect parameters,rotors and support parameters and inter-shaft bearing parameters on the amplitude-frequency characteristics of the system are *** results show that there are two main resonance peaks and four abnormal resonance peaks on the amplitude-frequency response curve of the dual-rotor with a local defect on the inner ring of the inter-shaft *** analyzing the vibration response of the abnormal resonance peaks,it is found that the first two abnormal resonances are caused by the combined resonance,which are related to the inner ring fault and the rotational speed of high or low pressure rotors,and the last two resonances are caused by the induced resonance of the inner ring *** the same time,when the parameters of defect,rotors and support and inter-shaft bearing change,the resonance of the system also shows the corresponding change law.

关键词： Combination resonance Dual-rotor system Inter-shaft bearing Local defect Nonlinear resonance

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Crustal deformation of Asia-Pacific area de-termined by the GPS data of APRGP97~ APRGP99

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Acta Seismologica Sinica(English Edition) 2001年第3期14卷 280-292页

作者： cheng Zong-yi 1. Shanghai Observatory Chinese Academy of Sciences 200030 Shanghai China

Using the pseudo-nonfiducial method of regional net, we have treated the GPS data of APRGP97, APRGP98 and APRGP99 by means of GIPSY software. The precision of coordinates obtained by us for most sites is 1-2 mm for north-south component and 2-5 mm for west-east component and 5-10 mm for vertical component, respectively. We have also obtained preliminarily moving velocities of 84 sites of Asia-Pacific area in ITRF97 frame. Based on the plate motion model derived from ITRF97, we have obtained the deformation velocity of the 84 sites relative to the plate in that they reside and preliminarily analyzed the motions of these sites relative to Eurasian plate.

关键词： GPS crustal deformation plate motion pseudo-nonfiducial P227

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Borophene gas sensor

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Nano Research 2022年第3期15卷 2537-2544页

作者： Chuang hou Guoan Tai yi Liu Xiang Liu The State Key Laboratory of Mechanics and Control of Mechanical Structures and Laboratory of Intelligent Nano Materials and Devices of Ministry of Education College of Aerospace EngineeringNanjing University of Aeronautics and AstronauticsNanjing 210016China

High-performance gas sensing devices have been extensively studied in industrial production,clinical medicine and environmental *** the materials used to fabricate gas sensors,two-dimensional(2D)materials are viewed as favorable candidate sensing materials because of their high surface-to-volume ratios,abundant surface activity,defect ***,gas sensors based on the previously reported 2D materials have some disadvantages such as poor air-stability and slow dynamic ***,borophene,as a unique 2D material,has been theoretically predicted to have excellent gas sensing characteristic,especially for nitrogen dioxide(NO_(2)).However,the gas sensing property of borophene has not been still reported ***,we report that a chemiresistive sensor device based on borophene shows high sensitivity,fast response,high selectivity,good flexibility and long-time *** is found that the sensor has a low experimental detection limit of around 200 ppb,a large detection range from 200 ppb to 100 ppm,and fast response time of 30 s and recovery time of 200 s at room temperature,which are remarkably superior to those of reported 2D *** underlying NO_(2) sensing mechanism of borophene is revealed by first-principles *** line with theoretical predication,it has also been confirmed experimentally that the borophene-based sensor has a unique selectivity to NO_(2) compared with other common ***,the sensor also displays superior flexibility and stability under different bending *** study shows excellent electronic and sensing characteristic of borophene,which indicates that it has great potential application value in high-performance sensing and detection in the future.

关键词： borophene gas sensor charge transfer wearable application density functional theory

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Transport of Propylene Carbonate-LiTFSI Electrolytes in P(VDF-HFP)Using Time-resolved ATR-FTIR Spectroscopy:Diffusion Coefficients and Molecular Interactions

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Chinese Journal of Polymer Science 2021年第8期39卷 975-983,I0005页

作者： Hui-Xian Li Lei hou Pei-yi Wu National Engineering Research Center for Dyeing and Finishing of Textiles College of ChemistryChemical Engineering and BiotechnologyDonghua UniversityShanghai 201620China

The time-resolved attenuated total reflectance-Fourier transform infrared(ATR-FTIR)spectroscopy is employed to investigate the transport mechanism of gel electrolytes by monitoring the diffusion behavior of propylene carbonate-lithium bis(trifluoromethylsulfonyl)imide(PC-LiTFSI)solution through poly(vinylidene fluoride-co-hexafluoropropylene)(P(VDF-HFP))*** behavior has been observed for both TFSr and *** temperature leads to faster diffusion of TFSI'and PC,which could be related to the increased free volume in P(VDF-HFP)matrix and rapid molecular movements upon *** molecular interactions among LiTFSI,PC and P(VDF-HFP)have been *** the diffusion process,PC molecules,in the form of small clusters,can firstly diffuse through the P(VDF-HFP)film and interact with P(VDF-HFP)by dipole-dipole interaction,acting as the ***,Li+diffuses into P(VDF-HFP)with the help of ion-dipole interactions between Li+and C=0 of ***,TFSI-diffuses through the polymer matrix in solvation *** addition,slight ion-dipole interactions between Li+and P(VDF-HFP)have been observed as *** in this work contribute to a better understanding of transport process in gel polymer electrolytes for lithium-ion batteries and support the development of improved gel polymer electrolytes by rationally regulating molecular interactions.

关键词： ATR-FTIR spectroscopy Gel polymer electrolyte Transport mechanism Molecular interaction Diffusion coefficient

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Dynamic optimization of 1,3-propanediol fermentation process:A switched dynamical system approach

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Chinese Journal of Chemical Engineering 2022年第4期35卷 192-204页

作者： Xiang Wu Yuzhou hou Kanjian Zhang Ming cheng School of Mathematical Sciences Guizhou Normal UniversityGuiyang 550001China School of Life Sciences Guizhou Normal UniversityGuiyang 550001China School of Electrical Engineering Southeast UniversityNanjing 210096China School of Automation Southeast UniversityNanjing 210096China Key Laboratory of Measurement and Control of CSE Ministry of EducationSoutheast UniversityNanjing 210096China

This paper considers a dynamic optimization problem(DOP)of 1,3-propanediol fermentation process(1,3-PFP).Our main contributions are as ***,the DOP of 1,3-PFP is modeled as an optimal control problem of switched dynamical *** the existing switched dynamical system optimal control problem,the state-dependent switching method is applied to design the switching ***,in order to obtain the numerical solution,by introducing a discrete-valued function and using a relaxation technique,this problem is transformed into a nonlinear parameter optimization problem(NPOP).Although the gradient-based algorithm is very efficient for solving NPOPs,the existing algorithm is always trapped in a local minimum for such problems with multiple local ***,in order to overcome this challenge,a gradient-based random search algorithm(GRSA)is proposed based on an improved gradient-based algorithm(IGA)and a novel random search algorithm(NRSA),which cannot usually be trapped in a local *** convergence results are also established,and show that the GRSA is globally ***,a DOP of 1,3-PFP is provided to illustrate the effectiveness of the GRSA proposed by this paper.

关键词： Process control Optimization Mathematical modeling Switched system State-dependent switching Global optimization

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Effect of Vacuum Pressure on the Initiation and Propagation of Pitting Corrosion of 2205 Duplex Stainless Steel in Concentrated Seawater

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Acta Metallurgica Sinica(English Letters) 2022年第6期35卷 1023-1033页

作者： Yong Yang Xue-Ling hou Mou-cheng Li Institute of Materials School of Materials Science and EngineeringShanghai UniversityShanghai 200072China

Pitting initiation and stable propagation behaviors of 2205 duplex stainless steel were investigated in the hot concentrated seawater under vacuum pressures by potentiostatic polarization. Both applied potentials and vacuum pressures greatly influence the pitting corrosion. Higher potentials lead to much faster stable pitting initiation and growth rates in both static(101.3 kPa) and dynamic(28.4 kPa) solutions. The pressure reduction can also accelerate the pitting initiation rate. However, the boiling of solution can influence the pitting propagation mechanism. The dynamic actions of boiling bubbles are unfavorable to the pit propagation and result in the formation of relatively smooth pit bottom without secondary pits.

关键词： Duplex stainless steel Stable pitting Vacuum pressure Hot concentrated seawater Potentiostatic polarization

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